You know there’s always things in life that you have to do despite the fact that you know for certain that the outcome is going to be messy, painful, humiliating or all three. Going to the dentist, asking someone out for the first time, breaking up a stag do outside the Bar Rumba on a Saturday night and, now, chasing a suspect through a hospital while wearing an open-backed hospital gown.

I went straight for the stairs because either Zach would hit the lifts, in which case I could beat him down; or he’d go for the stairs, in which case I’d be right behind him. When I pushed my way through the heavy fire doors there was no sign of him on the staircase, so I went down three steps at a time pausing only to scream loudly when I stubbed my toe halfway to the bottom.

Lesley says that the key to a successful chase is to know where the suspect is running to. Even if you don’t know their ultimate destination you should be able to make an educated guess about where the next choke point is. In Zach’s case, this was the hospital lobby, which is the only public way in or out. So that’s where I went first. Unfortunately, it’s got two exits at opposite ends to each other and what with the icy road conditions, the onset of winter flu and some pretty aggressive full contact shopping, it was full of the walking wounded and their hangers-on.

If Zach had been sensible enough to walk slowly and calmly out he would have got away. But, luckily for me, he was still running when he went out the north exit and all I had to do was follow the yelps of outrage as he pushed through the crowd. They yelled even louder when I steamed past in pursuit, what with me being a half-naked IC3, albeit in winter plumage. They came to all the wrong conclusions and scattered out of my way.

I ran down the wide flight of steps in front of the hospital, staggered once as my bare heel skidded on a bit of rotting ice, recovered and looked right and left. Unless you’re heading for the hospital, that particular stretch of pavement isn’t good for anything except inhaling exhaust fumes – which meant Zach was easy to spot, on my left, still running.

I went after him with my feet reminding me at every step why I spend all that money on trainers. The exertion kept me warm, but a cold breeze around my bum reminded me that I was short in the trouser department – that and the wolf whistle I got as I rounded the corner into Tottenham Court Road.